I received my Master’s degree in chemical engineering from SU, USA. I worked as a writer and researcher for Fortune 500 company clients.
The facts of today's climate
In October 2018, the Intergovernmental Panel on Climate Change (IPCC) set out a warning to reduce carbon dioxide (CO2) and other greenhouse gas emissions (GHG) within the next 12 years to avoid depletion of the ecosystem. We already see the consequence of global warming with increases in global surface temperature and changes in the frequency of weather events like rainfall patterns, heat waves, hurricanes, extreme wildfires, and many more. Today we largely depend on fossil fuels for energy, but the fact is that around 80% of the carbon emissions come from fossil fuel energy sectors like coal, oil, and gas industries. Fossil fuels are indeed limited resources, and we will run out of them one day. But, climate change is happening at a faster rate than fossil fuel extinction. We will have to eventually find alternate fuel and a way to reduce carbon emissions to successfully keep global average temperature increases below our 1.5°C limit.
How can we reduce CO2 emissions from the current industries and also our dependence on fossil fuels?
The solution might come from the world of algae. Recently companies are developing algae bioreactors to convert carbon emissions from industries into biofuel and other useful by-products. Hypergiant, Spitterwerk Architects, Colt, Strategic Science Consult, and ARUP, Algaewheel, Sapphire Energy, Solazyme, to name a few.
So why this technology?
Carbon capture technology to capture industrial gas emissions has been around for a while. These conventional capture methods use corrosive solvent absorbents in the absorption column, and pipelines to transport the CO2 into underground reservoir rocks. But there is still a chance of CO2 leakage from the deep reservoir. This method is high on cost and energy-intensive due to more equipment and materials used.
The Solution coming from the world of algae
The algae technology eliminates the challenge associated with the existing methods. Algae in the bioreactor use the minimum resource; carbon emissions from the industries and light just like plants to produce biofuel. Algae has high lipid content 50-70% and has higher biofuel productivity (up to 100 times) as compared to the lignocellulosic non-food crops like switchgrass used in the second-generation biofuel production. This means algae is capable of higher CO2 consumption and more biofuel production (an increase of algal biomass productivity per acre). It is easier to facilitate the pretreatment process due to the absence of lignocellulosic materials in the algae cell wall reducing overall production cost.
From a sustainability point of view, algae are not cultivated on land which is used for food crops and doesn't require huge water resources as compared to the food crops for biofuel production. Since algae are not edible food they also do not affect the human and animal food chain. The tiny plants can be grown in higher quantities per square foot of land, making land available for other purposes and have a strong potential for scalability. So the technology gives us an algae-based biofuel emitting much less greenhouse-effect gases when we burn it in our vehicle and interesting by-products like nutrient-rich high-protein food sources, fertilizers, plastics, cosmetics that are non-cancerous and non-toxic.
Cost analysis and Future Works
While the solution seems very efficient, it has to be affordable for people. One study claims they can capture direct flue gas, using a tubular photobioreactor for algae growth, to produce 47.1 MM gallons of green diesel production per year at $6.33/gal corresponding to GWP of 108.7 kg CO2‐eq per gallon.
While, researchers at Pacific Northwest National Laboratory’s (PNNL’s) Marine Sciences Laboratory in Sequim, Washington, aim to lower the cost of producing algae-based biofuels to $3/gasoline gallon equivalent by 2030. They promise to do so by cultivating highly productive strains of algae.
Research and development are addressing the critical challenges so that sustainable algae technology can provide us with an alternative eco-friendly fuel while efficiently capturing and minimizing CO2 emissions.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2021 Nikita Nandakumar Thattamprambil